Type of soil
Rocky ground allows for a good, solid base for your house, but it’s a pain to dig. Plan your house so that there is as little digging as possible. Filling in is easier than cutting through bedrock.

Soft ground is not as stable, and your efforts should revolve around making your foundation as strong as possible. The advantage is that you can make your home partially underground; the earth’s thermal mass is better than any insulation you can buy.

There are some types of soil that are ill suitable for building, such as clay and silt. Study the characteristics of your soil. Consider how much it shifts and sinks under weight, and how it reacts with frost and water.

Type of land
If you have flat land, you will have less work to do on leveling a building site. However, you do not want to build in a flood plain. If there’s no natural drainage, you will have to provide some, or start looking into elevating your house.

Hills provide natural drainage, but also a stronger flow of water, so direct it well. The steepness of the slope will determine how much you have to cut out or fill in to level your building site. If you have to cut out a lot, you might consider have steps in your house, so that some rooms, or areas of a room, are raised slightly above others.

If you have a choice, build on the southern face of a hill. You will be more protected from cold, northern winds, and have more access to the warmth of the sun. A northern face will keep your house in the shade, especially in winter, when the sun is lower in the southern skies. This will increase your need for additional heating.

Climate
If you can think about your heating and cooling systems before you start to plan your house, you can save a lot of expense. The more the house is built to fit the environment, the more comfortable the ambient, natural temperature will be. For example, we see temperatures of 120ºF in summertime, but our house has no air-conditioning. We have windows and a vent system that ensure airflow and keep the place cool (we have a fan for the rare days that it is completely still on our hill). We also have thick adobe walls, which, in summertime, never see the sun, because of porches and eaves. In the winter, it gets cold, and we want the sun to warm the adobe walls. So we made the eaves hang out far enough that they block the sun in summer, yet in winter, when the sun’s path is lower in the southern skies, the sun hits the adobe all day long. Same with the porch on the east side: its roof is made up of vining plants, watered by the kitchen sink. In summer, their leaves are thick and offer significant shade; in winter, the leaves die down and the sun can shine through.

Every climate is different. Study the weather patterns in your area and build your home to withstand the extremes, whether they are heat, cold, high winds, hail storms, etc. For example, if we lived in a hurricane zone, we would live underground or build a concrete dome.

Additional Resources:

• Green Home Building - Complete home building systems
• GreenBuilder - sustainable sources
• Earthships - An integrated system with the gardens built into the home
• US Green Building Council - News and information about the green building industry